import itertools

lst1 = [1, 2, 3]
lst2 = [4, 5, 6]
lst3 = [7, 8, 9]
for i in itertools.chain(lst1, lst2, lst3):
	print(i)

result2 = itertools.chain("abc", lst1)
print(result2)
print(list(result2))
